Earnings Per Share Narrative (Details) - shares	3 Months Ended		9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Outstanding stock options (in shares)	2,083,302	2,500,000	2,083,302	2,500,000	2,193,502
Antidilutive securities excluded from EPS computation (in shares)	500,000	1,200,000	400,000	1,200,000
Performance Vested Restricted Stock Units
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
PVRSUs excluded from EPS calculation due to performance conditions not met (in shares)			297,548	235,980